stops storing the whole fieldids weights map when no searchable are defined

milli/src/fieldids_weights_map.rs

@@ -4,7 +4,7 @@ use std::collections::HashMap;
 
 use serde::{Deserialize, Serialize};
 
-use crate::{FieldId, Weight};
+use crate::{FieldId, FieldsIdsMap, Weight};
 
 #[derive(Debug, Default, Serialize, Deserialize)]
 pub struct FieldidsWeightsMap {
@@ -19,6 +19,13 @@ impl FieldidsWeightsMap {
         self.map.insert(fid, weight)
     }
 
+    /// Create the map from the fields ids maps.
+    /// Should only be called in the case there are NO searchable attributes.
+    /// The weights and the fields ids will have the same values.
+    pub fn from_field_id_map_without_searchable(fid_map: &FieldsIdsMap) -> Self {
+        FieldidsWeightsMap { map: fid_map.ids().map(|fid| (fid, fid)).collect() }
+    }
+
     /// Removes a field id from the map, returning the associated weight previously in the map.
     pub fn remove(&mut self, fid: FieldId) -> Option<Weight> {
         self.map.remove(&fid)

milli/src/index.rs

@@ -436,11 +436,20 @@ impl Index {
 
     /// Get the fieldids weights map which associates the field ids to their weights
     pub fn fieldids_weights_map(&self, rtxn: &RoTxn) -> heed::Result<FieldidsWeightsMap> {
-        Ok(self
+        self.main
-            .main
             .remap_types::<Str, SerdeJson<_>>()
             .get(rtxn, main_key::FIELDIDS_WEIGHTS_MAP_KEY)?
-            .unwrap_or_default())
+            .map(Ok)
+            .unwrap_or_else(|| {
+                Ok(FieldidsWeightsMap::from_field_id_map_without_searchable(
+                    &self.fields_ids_map(rtxn)?,
+                ))
+            })
+    }
+
+    /// Delete the fieldsids weights map
+    pub fn delete_fieldids_weights_map(&self, wtxn: &mut RwTxn) -> heed::Result<bool> {
+        self.main.remap_key_type::<Str>().delete(wtxn, main_key::FIELDIDS_WEIGHTS_MAP_KEY)
     }
 
     pub fn searchable_fields_and_weights<'a>(
@@ -629,29 +638,13 @@ impl Index {
     pub(crate) fn put_all_searchable_fields_from_fields_ids_map(
         &self,
         wtxn: &mut RwTxn,
-        user_fields: Option<&[&str]>,
+        user_fields: &[&str],
         fields_ids_map: &FieldsIdsMap,
     ) -> Result<()> {
-        // Special case if there is no user defined fields.
-        // Then the whole field id map is marked as searchable.
-        if user_fields.is_none() {
-            let mut weights = self.fieldids_weights_map(wtxn)?;
-            let mut searchable = Vec::new();
-            for (weight, (fid, name)) in fields_ids_map.iter().enumerate() {
-                searchable.push(name);
-                weights.insert(fid, weight as u16);
-            }
-            self.put_searchable_fields(wtxn, &searchable)?;
-            self.put_fieldids_weights_map(wtxn, &weights)?;
-            return Ok(());
-        }
-
-        let user_fields = user_fields.unwrap();
-
         // We can write the user defined searchable fields as-is.
         self.put_user_defined_searchable_fields(wtxn, user_fields)?;
 
-        let mut weights = self.fieldids_weights_map(wtxn)?;
+        let mut weights = FieldidsWeightsMap::default();
 
         // Now we generate the real searchable fields:
         // 1. Take the user defined searchable fields as-is to keep the priority defined by the attributes criterion.
@@ -682,6 +675,7 @@ impl Index {
     pub(crate) fn delete_all_searchable_fields(&self, wtxn: &mut RwTxn) -> heed::Result<bool> {
         let did_delete_searchable = self.delete_searchable_fields(wtxn)?;
         let did_delete_user_defined = self.delete_user_defined_searchable_fields(wtxn)?;
+        self.delete_fieldids_weights_map(wtxn)?;
         Ok(did_delete_searchable || did_delete_user_defined)
     }
 

milli/src/update/settings.rs

@@ -490,7 +490,7 @@ impl<'a, 't, 'i> Settings<'a, 't, 'i> {
 
                 self.index.put_all_searchable_fields_from_fields_ids_map(
                     self.wtxn,
-                    Some(&names),
+                    &names,
                     &fields_ids_map,
                 )?;
                 self.index.put_fields_ids_map(self.wtxn, &fields_ids_map)?;
@@ -1228,11 +1228,13 @@ impl InnerIndexSettings {
             .map(|searchable| searchable.iter().map(|s| s.as_str()).collect::<Vec<_>>());
 
         // in case new fields were introduced we're going to recreate the searchable fields.
+        if let Some(searchable_fields) = searchable_fields {
             index.put_all_searchable_fields_from_fields_ids_map(
                 wtxn,
-            searchable_fields.as_deref(),
+                &searchable_fields,
                 &self.fields_ids_map,
             )?;
+        }
         let searchable_fields_ids = index.searchable_fields_ids(wtxn)?;
         self.searchable_fields_ids = searchable_fields_ids;
 
@@ -1513,7 +1515,7 @@ mod tests {
     use crate::error::Error;
     use crate::index::tests::TempIndex;
     use crate::update::ClearDocuments;
-    use crate::{Criterion, Filter, SearchResult};
+    use crate::{db_snap, Criterion, Filter, SearchResult};
 
     #[test]
     fn set_and_reset_searchable_fields() {
@@ -1542,6 +1544,17 @@ mod tests {
 
         wtxn.commit().unwrap();
 
+        db_snap!(index, fields_ids_map, @r###"
+        0   id               |
+        1   name             |
+        2   age              |
+        "###);
+        db_snap!(index, searchable_fields, @r###"["name"]"###);
+        db_snap!(index, fieldids_weights_map, @r###"
+        fid weight
+        1   0   |
+        "###);
+
         // Check that the searchable field is correctly set to "name" only.
         let rtxn = index.read_txn().unwrap();
         // When we search for something that is not in
@@ -1565,6 +1578,19 @@ mod tests {
             })
             .unwrap();
 
+        db_snap!(index, fields_ids_map, @r###"
+        0   id               |
+        1   name             |
+        2   age              |
+        "###);
+        db_snap!(index, searchable_fields, @r###"["id", "name", "age"]"###);
+        db_snap!(index, fieldids_weights_map, @r###"
+        fid weight
+        0   0   |
+        1   1   |
+        2   2   |
+        "###);
+
         // Check that the searchable field have been reset and documents are found now.
         let rtxn = index.read_txn().unwrap();
         let fid_map = index.fields_ids_map(&rtxn).unwrap();